CVE-2025-21589

Session Smart Router, Session Smart Conductor, WAN Assurance Router: API Authentication Bypass vulnerability

Published Jan 27, 2026 CVSS 4.0 · 9.3 Critical EPSS 1.5% KEV · Not listed
Description
An Authentication Bypass Using an
Alternate Path or Channel vulnerability in Juniper Networks Session Smart
Router may allows a network-based attacker to bypass authentication
and take administrative control of the device.

This issue affects Session Smart Router: 



* from 5.6.7 before 5.6.17, 
* from 6.0 before 6.0.8 (affected from 6.0.8),

* from 6.1 before 6.1.12-lts, 
* from 6.2 before 6.2.8-lts, 
* from 6.3 before 6.3.3-r2; 




This issue affects Session Smart Conductor: 



* from 5.6.7 before 5.6.17, 
* from 6.0 before 6.0.8 (affected from 6.0.8),

* from 6.1 before 6.1.12-lts, 
* from 6.2 before 6.2.8-lts, 
* from 6.3 before 6.3.3-r2; 




This issue affects WAN Assurance Managed Routers: 



* from 5.6.7 before 5.6.17, 
* from 6.0 before 6.0.8 (affected from 6.0.8),

* from 6.1 before 6.1.12-lts, 
* from 6.2 before 6.2.8-lts, 
* from 6.3 before 6.3.3-r2.

Remediation

Vendor Solution

The following software releases have been updated to resolve this issue: Session Smart Router: SSR-5.6.17, SSR-6.1.12-lts, SSR-6.2.8-lts, SSR-6.3.3-r2 and subsequent releases. It is suggested to upgrade all affected systems to one of these versions of software. In a Conductor-managed deployment, it is sufficient to upgrade only the Conductor nodes and the fix will be applied automatically to all connected routers. As practical, the routers should still be upgraded to a fixed version however they will not be vulnerable once they connect to an upgraded Conductor. Router patching can be confirmed once the router reaches the “running" (on 6.2 and earlier) or “synchronized” (on 6.3+) state on the Conductor".   This vulnerability has been patched automatically on devices that operate with WAN Assurance (where configuration is also managed) connected to the Mist Cloud. As practical, the routers should still be upgraded to a version containing the fix. It is important to note that when the fix is applied automatically on routers managed by a Conductor or on WAN assurance, it will have no impact on data-plane functions of the router. The application of the fix is non-disruptive to production traffic. There may be a momentary downtime (less than 30 seconds) to the web-based management and APIs.


Vendor Workaround

There are no known workarounds for this issue.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Juniper
Juniper session Smart Conductor
Juniper session Smart Router
Juniper wan Assurance Managed Router
Vendors & Products Juniper
Juniper session Smart Conductor
Juniper session Smart Router
Juniper wan Assurance Managed Router
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description An Authentication Bypass Using an Alternate Path or Channel vulnerability in Juniper Networks Session Smart Router may allows a network-based attacker to bypass authentication and take administrative control of the device. This issue affects Session Smart Router:  * from 5.6.7 before 5.6.17,  * from 6.0 before 6.0.8 (affected from 6.0.8), * from 6.1 before 6.1.12-lts,  * from 6.2 before 6.2.8-lts,  * from 6.3 before 6.3.3-r2;  This issue affects Session Smart Conductor:  * from 5.6.7 before 5.6.17,  * from 6.0 before 6.0.8 (affected from 6.0.8), * from 6.1 before 6.1.12-lts,  * from 6.2 before 6.2.8-lts,  * from 6.3 before 6.3.3-r2;  This issue affects WAN Assurance Managed Routers:  * from 5.6.7 before 5.6.17,  * from 6.0 before 6.0.8 (affected from 6.0.8), * from 6.1 before 6.1.12-lts,  * from 6.2 before 6.2.8-lts,  * from 6.3 before 6.3.3-r2.
Title Session Smart Router, Session Smart Conductor, WAN Assurance Router: API Authentication Bypass vulnerability
Weaknesses CWE-288
References
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
juniper
Published
Updated
Jan 27, 2026, 9:28 PM
Reserved
Dec 26, 2024, 2:47 PM
Status
Deferred
Published
Jan 27, 2026, 9:15 PM
Modified
Jun 17, 2026, 8:43 AM